Sun vs Perm

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The Sun is the star at the center of the Solar System. It is a nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy mainly as light and infrared radiation. It is by far the most important source of energy for life on Earth. Its diameter is about 1.39 million kilometres (864,000 miles), or 109 times that of Earth, and its mass is about 330,000 times that of Earth. It accounts for about 99.86% of the total mass of the Solar System. Roughly three quarters of the Sun's mass consists of hydrogen (~73%); the rest is mostly helium (~25%), with much smaller quantities of heavier elements, including oxygen, carbon, neon, and iron.The Sun is a G-type main-sequence star (G2V) based on its spectral class. As such, it is informally and not completely accurately referred to as a yellow dwarf (its light is closer to white than yellow). It formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center, whereas the rest flattened into an orbiting disk that became the Solar System. The central mass became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process.

In its core the Sun currently fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second as a result. This energy, which can take between 10,000 and 170,000 years to escape the core, is the source of the Sun's light and heat. When hydrogen fusion in its core has diminished to the point at which the Sun is no longer in hydrostatic equilibrium, its core will undergo a marked increase in density and temperature while its outer layers expand, eventually transforming the Sun into a red giant. It is calculated that the Sun will become sufficiently large to engulf the current orbits of Mercury and Venus, and render Earth uninhabitable – but not for about five billion years. After this, it will shed its outer layers and become a dense type of cooling star known as a white dwarf, and no longer produce energy by fusion, but still glow and give off heat from its previous fusion. The enormous effect of the Sun on Earth has been recognized since prehistoric times. The Sun has been regarded by some cultures as a deity. The synodic rotation of Earth and its orbit around the Sun are the basis of solar calendars, one of which is the predominant calendar in use today.

Source: Wikipedia

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Perm (Russian: Пермь, IPA: [pʲɛrmʲ]), previously known as Yagoshikha (Ягошиха) (1723–1781), and Molotov (Мо́лотов) (1940–1957), is the largest city and the administrative centre of Perm Krai, Russia. The city is located on the banks of the Kama River, near the Ural Mountains, covering an area of 799.68 square kilometres (308.76 square miles), with a population of over 1 million residents. Perm is the fourteenth-largest city in Russia, and the fifth-largest city in the Volga Federal District. In 1723, a copper-smelting works was founded at the village of Yagoshikha. In 1781 the settlement of Yagoshikha became the town of Perm. Perm's position on the navigable Kama River, leading to the Volga, and on the Siberian Route, across the Ural Mountains helped it become an important trade and manufacturing centre. It also lay along the Trans-Siberian Railway.

Perm grew considerably as industrialization proceeded in the Urals during the Soviet period, and was named Molotov in honour of Vyacheslav Molotov. After the dissolution of the Soviet Union, the city returned to its historical name, and became the administrative centre of Perm Krai. Modern Perm is still a major railway hub and one of the chief industrial centres of the Urals region. The city's diversified metallurgical and engineering industries produce equipment and machine tools for the petroleum and coal industries, as well as agricultural machinery. A major petroleum refinery uses oil transported by pipeline from the West Siberian oilfields, and the city’s large chemical industry makes fertilizers and dyes. The city’s institutions of higher education include the Perm A.M. Gorky State University, founded in 1916.

Source: Wikipedia